The Devil Among Us
by Sleepydeeps
Summary: While battling his own personal demons, Sherlock enters a deadly game of cat and mouse. Will he be able to protect the people close to his heart, or will he destroy himself from the inside before he gets the chance? Slow burning Sherlolly, John/Mary. Set immediately after The Abominable Bride.
1. The Game Begins Anew

John replayed the scene in the small jet in his head, over and over agin as the trio sat silently in the black of the black town car, courtesy of Mycroft. He watched Sherlock as he seemed to vibrate in his seat, eyes closed and apparently deep in thought. Irritation gripped him as he suddenly struggled not to clock his best friend right in his nose. Mary noticed and placed a hand on his arm, comforting him slightly. He looked to her, his eyes displaying his dismay with the situation. John brought his attention back to Sherlock, wondering if he was in his Mind Palace or just riding out whatever high he was on.

"So, what now?" John asked in a tight voice.

"Obviously, we wait. No doubt that Mycroft has his resources scouring the world for the source of the signal. This hoax was obviously meant to-"

"No, you bloody idiot," John cut Sherlock off abruptly and leaned forward, his anger coming off him in waves, "Using again, Sherlock? This time it wasn't 'for the case', was it? We know you've taken these drugs long before that message was broadcast. How long has this been going on, Sherlock?"

"Oh honestly, John, this is really not the time for-"

John fist slammed into Sherlock's nose and his head snapped back against the headrest. "I don't care, Sherlock. I want to know and I want to know right now. How long has this been going on?"

Sherlock glared at him, his head tilted back as he tried to slow the bleeding. Mary reached into her bag and gave him a tissue. He pressed it against his nostrils and sighed. "It matters not, John. I have always been in control of my drug usage. I merely used it to clear my mind, to find the answers."

"Find the answers? So this goes back before killing Magnussen then?"

Sherlock was silent, still holding the tissue to his upturned nose. He knew John was upset, but couldn't he understand? The drugs dulled his senses and allowed him to go delve further into his Mind Palace, a place that held the answers he was looking for.

"It was needed for the case. Magnussen had the upper hand in a very dangerous game. A game that you and Mary couldn't afford to lose."

"Look what we have to show for it then. Had this little event not occurred, you'd be in route to your death, Sherlock. Come to think of it, we still might be heading there. The only difference is instead of whatever was waiting for you in Eastern Europe, it'll be a needle in your arm!" John shouted. Mary's had still on his arm, though he wasn't sure if it was for comfort, or to stop him from delivering another punch to Sherlock's face.

Sherlock scoffed, "I've heard enough from Mycroft about this subject to last a lifetime. I daresay that I don't need a lecture from you. Besides, our attention needs to be on whoever is behind this hoax."

"Sherlock, we're only concerned. You're our friend and we love you. Don't get lost in this and destroy your life," Mary added in a tender voice befitting of a soon-to-be mother. Sherlock let out another scoff and chewed back a scything retort, choosing to stare out the window and nurse his still bleeding nose. He could feel their eyes on him, one filled with anger and the other with worry. Choosing not to respond, he stayed silent.

John let out a frustrated sigh. He knew that chewing out Sherlock right now wasn't productive, but it nothing to quell his anger. He thought about punching Sherlock again, but he doubted it would help. John put a hand on Mary's knee, hoping that the contact with his wife would curb his emotions. This wasn't the first time he's had to deal with Sherlock's addiction. Finding Sherlock in the drug den when he was bringing Issac back home. He hadn't known then what Sherlock was on and his anger subsided by the time Molly had reported the positive results of the drug test. A small smile tried to tug at the corners of his mouth as he remembered the smack to the face Molly had delivered afterward. The ghost of a smile died as quickly as it came. It was different now that he knew of the extent of Sherlock's drug abuse. He was honestly surprised that Sherlock was still alive after what he had taken.

The car ride to 221 Baker Street carried on in silence. Sherlock all but ran out of the car before it had come to a halt near the curb. Swinging open the door and hurrying up the stairs, leaving John and Mary behind without a second thought. Settling on the couch, he closed his eyes and planning out what his next move would be against this impostor that used Moriarty's face as a cover. The drugs were leaving his system as he had taken them ours before he'd headed to the airport with Mycroft. He shivered even though the temperature in the apartment was pleasant.

When his eyes finally opened, he was met with darkness. Sherlock could make out the forms of the Watsons sitting in the arm chairs in front of him, fast asleep. A cup of tea sat on the table next to a neatly folded pair of pajamas. Snatching the pajamas, he made his way to the bathroom for a quick shower. He washed away the sweat that came with coming down and the dried blood from his bruised nose, letting the water hit his head and bead down his back. Stepping out of the shower and dressing, he made his way back to the sitting room to find John and Mary awake. He laid back down on the couch and gazed up at the celling.

"You may leave now. Mycroft has already sent someone, likely Mrs. Hudson, to clear this place of any nasty habits that lay hidden." It was tradition for every relapse he had. His irritation towards Mycroft intensified. "The sooner, the better. It would be a shame for Mary to put anymore unnecessary strain to my chair. I'd hate for it to break under the strain."

"We aren't going anywhere and if you insult my pregnant wife again, I'll finish what I started and break your nose," John stood and walked to the kitchen. He grabbed a plate of full of food of the counter top and drooped it in front of Sherlock. "Mrs. Hudson dropped by with dinner. She's not happy by the way. Her search yielded results apparently. I'm sure you're already aware."

Sherlock ignored John and started eating. The stress of being exiled and the relief of being brought back did wonders for one's appetite.

"Moriarty's message. You said that you knew for sure that he was dead. If he's gone for good, who's behind this? Why would they do it?" asked Mary after Sherlock put his plate down and settled back against the couch.

"The who is unclear. Why, though, that's the intriguing part. Dismantling Moriarty's network after my supposed suicide was a large task. It spread far more than anyone could have imagined. From the common street thug to the inner workings of foreign governments, it heavily tainted anything it touched. After his death, there was a position to fill. Someone would rise to the top, only to be killed and replaced. A vicious cycle. This allowed me to break apart small cells all over the world without drawing too much attention to myself. Eventually, the network collapsed on itself. Nobody could quite fill Moriarty's shoes."

Sherlock stood and began pacing, "James Moriarty is being used as a face. The martyr for criminals everywhere. The message itself was a challenge directed at me. Soon, crime is going to spike, adding to the fear that is no doubt gripping London. They are showing off, letting me know its time to play."

"You said that you knew what their next move would be," stated John, his anger and irritation temporarily forgotten.

"Murder. Specifically, the murder of someone of high standing. The goal is to strike fear into the heart of the country. Once in the car, I took the liberty of making a list of potential victims. Mycroft has more than likely come to the same conclusion and issued a guard, not that it's going to help. For now, we wait. I'm sure the next message shall be delivered in a timely fashion."

Once again, silence fell upon 221B Baker Street.

DI Lestrade and Sergeant Donavan had arrived at the crime scene at the heart of London's Central Business District. The body had been found lying on a bench by someone that was living on the streets close by. Seemingly appearing out of thin air, according to the witness. Her hands crossed over the front of her chest, resting in the middle. They started question the witness which didn't reveal much.

"And you didn't see anyone in the area before?" asked Donavan, taking notes as the homeless man took a second to pull himself back together.

"No, ma'am. It's been awfully quiet tonight."

"Okay, thank you for your statement. If you happen to hear anything else, please contact Scotland Yard." With that, Lestrade and Donavan dismissed him and turned back to the crime scene. His voice stopped them.

"I've seen a lot of horrible things. Living on the streets be making it hard to avoid. Ain't never seen nothing like this before though," the man stopped and tried to collect himself before he continued on, "I really hope you catch the bastard. I reckon that no one deserves to die like that."

With that, the man walked away. Lestrade turned back to the body that was now surrounded by the forensics team, frowning as he tried to put everything together.

"Are you going to contact him?" asked Donavan, even though she already knew the answer.

"Yeah, I reckon we have to, given the circumstances. This is going to be a bloody circus," quipped Lestrade as he pulled out his phone to send Sherlock a text with their current location with the explanation of murder. There was no questioning that. It was murder.

Laying on the bench in the heart of London was Lady Elizabeth Smallwood. A large hole in her chest which her hands covered. Inside of it was, presumably her heart, which was burnt to a crisp.


	2. Burnt Out

**A/N:** Thank you so much for the support and reviews. It really pushes me to write more. With that being said, I'm not very happy with my portrayal of Sherlock so far. I'm hoping I can get into his character a little more in the future, but I really don't feel like its up to snuff just yet. Let's hope it gets better. Cheers!

The news of Lady Smallwood's gruesome murder spread like a wild fire. Plastered all over the front of every newspaper in the UK. Speculation ran wild on several news broadcasts, most trying to link the Lady's death to Moriarty's reappearance which one would assume was the intended result. A quiet panic set over London that was felt by every citizen. The streets weren't any less busy, but everyone seemed to be watching over their shoulder. If Lady Smallwood could be murdered, we're they really safe?

Shortly after leaving the crime scene The Watson's parted ways and left for their flat. Understandably so, the sun was starting to come up and unlike him, they needed sleep. Sherlock could recall John's heated gaze right before he got into the cab. A silent warning. Without saying a word, he climbed in and the cab drove off. Alone again, he hailed a cab. "St. Bart's."

The ride allowed him to go over the events in peace. Lady Smallwood's body mutilated, but more specifically, the charred heart in her chest put him on edge.

 _"I will burn you. I will burn the heart out of you!"_

It was clearly a message. It couldn't be anything else. Whoever was behind this had intended to finish Moriarty's work. The Watson's were in danger. Lestrade was in danger, as was Mrs. Hudson. As much as he loathed it, upon seeing the body, he had messaged Mycroft asking for protection for his friends. Oddly enough, Mycroft had accommodated without a snide comment or any air of superiority. It was almost as if he sympathized with Sherlock. A wave of guilt ran through him as he recalled the events on the plane, but quickly put it behind him. There were more important matters at hand. He needed to examine the body, to find any clues to the whereabouts of the party behind this.

The cab pulled up to St. Bart's, Sherlock paid his fare and made his way inside. The morgue was cold as always and he pulled his coat around him. To his surprise, Lestrade was sitting in a chair with a cup of coffee in his hand. Seeing Sherlock, he stood up and made his way over.

"Molly isn't hear today. Called off, so I figured I'd be here so they didn't toss you out on your arse," Lestrade flashed him a smirk.

"Don't you have more important things to do?" asked Sherlock as he picked up Lady Smallwood's file and started to review it.

"I think keeping you from being barred from the morgue is pretty high up there. This is a high profile murder, Sherlock. Much as I hate to admit it, you're probably the best chance we've got at figuring this out. I'll do whatever it takes to yield some results. Let's get started shall we?" he clapped and rubbed his hands together with a smile.

"Oh, do shut up, Lestrade. Why isn't Molly Hooper here? Doesn't she realize that she is the only pathologist here that's worth a damn? This report is dismal," Sherlock threw the file on the countertop and strode over to the body, flinging the sheet off.

"Well, she's probably a little mixed up right now, isn't she? Moriarty's return probably had a little more effect on her than most, you reckon?" Lestrade gave a disgusted look upon the mangled body.

Sherlock, who had been inspecting the edges of the hole in her chest with a magnifying lens, froze slightly. Surely, her involvement in faking his death wasn't known. Putting the thought out of his head, he didn't bother to give Lestrade a response. The DI stared slightly and sighed with a shake of his head.

The consulting detective worked in silence. Lestrade popped in and out as well as other hospital staff. He didn't even notice, his eyes glued to the microscope in front of him, analyzing traces of metal that was found in the wound. The cut itself was jagged, shavings of metal around the edges. Oxidized. The hole was made with a rust covered blade, most likely a dagger, judging by the site of the first incision. It was uneven and cuts all around the wound. Lady Smallwood had been alive and most definitely awake at the time of her murder.

Sherlock let out a frustrated sigh and pulled away from his work. He looked at the clock and noted that it was almost ten o'clock in the evening. There was nothing else here. He hadn't been able to determine anything, only that she suffered before her death. Useless! He flung the files across the room and slammed his fist down. His mind was muddled and his body was tormenting him. The ache for any kind of high coursed through him. Not making any headway did not help in the slightest.

He gathered his things and left the morgue, choosing to walk home instead of hailing a cab. The cool air bit at him and he pulled his coat tighter, shivering slightly but not entirely sure that the cold was the cause. Blocks away from Baker Street, he turned down a dark alleyway. Pressing his back against the wall, he closed his eyes and drew in deep breaths. His hand snaked into the pocket of his coat and fumbled over the small vial of morphine. Mycroft may have had his flat scoured, but they didn't bother to invade his personal space. His whole body was shaking, the deep breaths doing nothing to calm him. He pushed off the wall and started off in a brisk walk towards Baker Street.

Sherlock sat in the darkness of 221B, his eyes locked on the vial that rested on the mantle above the fireplace. Each time the thought of John's look of disappointment and Mary's worry made their way to the forefront of his brain, he looked away and closed his eyes, trying to shake away the guilt. He didn't deal with guilt well. To be honest, it was a relatively new feeling. Mycroft had expressed his worry and had always been there as Sherlock had come down from whatever he was on, but he never expressed his…feelings. He didn't want to disappoint his friends, but the urge was growing greater by the second. The excuse of using in need of solving a case was slowly becoming more and more of a lie. His body and mind were betraying him.

Before he knew it, a needle was resting against his arm. Not yet punctured, he stared at it. The feeling of letting down the ones he cared about coursed through him, but the need of the drug was greater. He pressed the needle into the vein and plunged the morphine in. The effect was immediate. It wasn't bliss and euphoria. No, he was way past that point. It was a clearing of the mind. His thoughts grew vivid and he withdrew into his mind palace, almost trapped there.

"Oh, Sherlock. A devil amongst the angels indeed."

Sherlock's eyes shot open, locking onto Moriarty's, who was sitting in John's chair across from him.

"So weak. So pathetic. You really should have done yourself a favor and actually jumped off the roof that day, Sherlock. The fall would have been fantastic."

Sherlock could only sit there and stare. It felt so real, but he knew it wasn't. This wasn't the first time he's confronted Moriarty since his death.

Moriarty threw his head back and started to laugh, "You know Sherlock, you've always been so transparent. I can look at you and know your every move. Your every thought."

"If that was the case, you'd be here and I'd be dead. Don't presume you know everything," Sherlock responded, losing himself to the hallucination.

"Really, Sherlock? Did you think I didn't know how that day was going to end? Sure, it would have been just lovely if you'd have actually jumped, but that wasn't my end game now, was it?" Moriarty grinned as he stood and walked over to the mantle, his hands picking up the skull that was covered in dust. He gave it a blow, cleaning it off.

"Your network was torn down. This hoax is nothing more than a desperate ploy to strike fear. An imitation of the real thing that will be stopped with haste." Sherlock's eyes were locked on Moriarty, not trusting himself to look away.

"I told you that day at the pool, Sherlock, that I would burn the heart out of you," Moriarty turned to look at Sherlock, still holding the skull, "That was always the plan. I knew I was going to meet my end on that rooftop. A step ahead as always. Jumping off a roof to escape a ruined image and to save your friends? A little too simple, don't you think? Not really my ideal death, no. No, Sherlock. NO!"

Moriarty threw the skull against the wall and it shattered to pieces. Suddenly, he was face to face with Sherlock, his breath hot against his face. A mad look in his eyes, "You've already started down the path I set, haven't you? You may not have "feelings", but we both know that's a lie. Doing what you've done couldn't have been easy on you. The killings take a toll, don't they? Don't they, Sherlock?"

Moriarty's tongue shot out and ran itself along Sherlock's face, "Yes, I can taste it. The nightmares. The horrible things you've done to stop a criminal mastermind. It's changed you. The thrill of the case no longer working for you, is it?"

He reached down and put the needle into Sherlock's hands. "You'll do what I've always meant for you to do. You'll burn, Sherlock. A devil can never live with the angels, Sherlock! YOU'RE MEANT TO BURN!"

Sherlock looked down to his now naked chest, filled with needles and rotten flesh. The skin suddenly caught fire and all he could do was scream.

"Sherlock! Sherlock, wake up!"

His eyes shot open as Mrs. Hudson was shaking him, he was gasping for breath and shaking. "Oh, dear, are you okay, Sherlock?"

He looked down to his chest, now fully clothed, and ran his hands over himself. Trying to control his breathing, he raised a hand to stop Mrs. Hudson's worrying. "I- I'm fine, Mrs. Hudson. I'm fine."

Sherlock didn't sound fine, but she let him be. She didn't notice the small case in between his leg and the seat that contained his habit, thankfully. "I'll just go get you a cuppa then, shall I?"

She left the room and Sherlock was left with his thoughts and shaky breathing. He stood and opened the draw to his desk, placing his kit away and hoping he wouldn't need it again. The phone in his pocket suddenly vibrated with a text message.

MOLLY HOOPER HAS BEEN ATTACKED. COME TO SCOTLAND YARD ASAP. -LESTRADE

Sherlock was out the door and hailing a cab without a second thought. A fear gripping his heart.

 _"You'll burn, Sherlock."_


End file.
